Autotransfusion systems are now widely accepted. The reason why is that there is significant importance placed upon post operative blood collection and reinfusion. Consequently, various systems have been developed to incorporate the collection and reinfusion of blood into a patient's body.
Generally, the withdrawal of blood is under vacuum from an operation site. A preset suction is utilized to pull and drain blood from the operation site. In doing this, there is an effort to maintain red blood cells to protect them from potential hemolysis. Also, efforts are made to protect the tissue from being damaged at the operation site while at the same time insuring proper withdrawal of the blood from the site.
In order to effectuate this, various efforts have been attempted to withdraw the blood into a blood bag and then reinfuse it into a patient's body. The withdrawal is under vacuum which can be provided by a vacuum source such as the normal vacuum within a hospital environment. Such vacuum sources are usually provided through vacuum pumps connected to a series of pipes that can be accessed near a patient's bed or within an operating room procedural area. Also, it is known to drain wound or operation sites without the use of vacuum by merely allowing them to drain into a drainage tube on a gravity basis.
Most autotransfusion devices rely upon pulling blood from a wound or operation site that is suctioned directly into a holding area such as a blood bag or a reservoir. It is oftentimes filtered and mixed with an anti-coagulant and then reinfused directly from the same unit or from a blood bag.
The use of reinfused blood lowers the cost of transfusion from banked blood. This in turn lowers the expense to the patient. Additionally, problems such as typing, screening, risks such as AIDS or cross matching of banked blood is substantially eliminated if reinfused blood is transfused to the patient.
Such systems that are currently available are set forth in various patents. One of these patents is U.S. Pat. No. 4,573,992 entitled An Apparatus For Receiving and Reinfusing Blood by Guenter H. Marx assigned to Solco Basel AG. This particular device incorporates a concertina-like container which once filled is compressed to reinfuse the blood into a patient. In effect, it operates as an expansion chamber withdrawing the blood under vacuum, and then re-compressing the chamber for infusion. The device specifically lacks utility with respect to a constant vacuum source that can be used in adjacent relationship with it. It also lacks proper filters, and an overall configuration that can be adapted for use in an easy and facile manner during autotransfusion with respect to orthopedic operations.
A later development by the assignee of the foregoing patent incorporates an improved reservoir with an inherent vacuum source. However, it lacks a vacuum source and other features that make this invention functional and, capable of being implemented in a facile manner. For instance the vacuum source is a bulb, that when squeezed relies upon the resilience of the rubber in the bulb to expand and provide a vacuum. It furthermore does not provide a multiple displacement vacuum pump function as does this invention.
Another patent, namely U.S. Pat. No. 4,767,417 for a drainage device for collecting liquids from a body cavity assigned to Boehringer Laboratories incorporates a withdrawal system for withdrawing fluids from a wound or operation site. A particular vacuum maintenance regulation chamber is incorporated as well as a blood bag concept. However, in this particular case there is no integrated vacuum system as in the applicant's invention herein of the type necessary to perform an orthopedic autotransfusion function.
U.S. Pat. No. 4,744,785 entitled Autotransfusion System assigned to C. R. Bard sets forth a collection bottle that can be used for salvaging blood and reinfusing it. There is no inference as to an integrated vacuum system that can be utilized as that of the applicants herein.
From a reading of the literature and the general format of the prior art, it is believed that the applicants' invention sets forth an integrated vacuum system which is new and unobvious over the prior art.
The applicants' integrated vacuum system and reservoir as well as the entire autotransfusion system incorporates an integrated vacuum source in the form of a positive displacement manual piston pump. A wall vacuum access port is also provided as an alternative vacuum source. The integrated manual vacuum pump assures portability and a steady source of vacuum at the site through a displacement piston pump means which can be in the form of a syringe. The vacuum is regulated by a regulation system to be within the proper operational norms.
A bellows pump having a spring loaded interiorly expandable chamber with check valves can also serve as an alternative embodiment for this invention.
The invention further incorporates check valves in an arrangement for providing the vacuum and the exhaust by use of the integrated manual vacuum pump. The check valves are particularly adaptable and useful in their configuration and the circuit in which they have been placed.
Integrated filters in the reservoir are provided in order to filter the blood. The filter is emplaced with a pressed fitting and is entrapped on the top and bottom thereby, limiting the requirement for bonding.
A vacuum indicator is provided by this invention to visually indicate the amount of vacuum within the reservoir of the system. This is performed by a rubber bellows or other expandable device that moves an indicator with respect to a pre-established scale.
A filtered release valve and a vent is provided in order to establish a proper vacuum and relief when desired.
Further features include a quick disconnect means with a check valve as well as a blood bag attachment for using a blood bag in conjunction with the reservoir of the system. Also, injection and sampling ports are provided with the option of being able to inject or withdraw fluids such as anti-coagulants into the reservoir.
Based upon the foregoing advantages it is believed that this invention is a significant step over the prior art as to its form and functional features.